Effect of lesioning dopamine, noradrenaline and 5-hydroxytryptamine pathways on tremorine-induced tremor and rigidity.

Abstract

The effects of lesioning monoamine pathways in the rat brain on tremorine-induced hind-limb tremor and rigidity were studied. Nigro-striatal and mesolimbic dopamine (DA) neurones were lesioned unilaterally by injecting 6-hydroxydopamine (6-OHDA) into the median forebrain bundle. Tremor was reduced in the contralateral leg and rigidity was prevented in the ipsilateral leg. Injection of 6-OHDA into the nucleus accumbens affected tremor but not rigidity. In general, nigral DA neurones may influence rigidity whilst mesolimbic DA neurones affect tremor. A unilateral locus coeruleus electrolesion which destroys noradrenaline (NA) fibres reduced both tremor and rigidity. A median raphe electrolytic lesion affecting 5-hydroxytryptamine (5-HT) neurones had no effect on tremor and rigidity, whereas lesioning the dorsal raphe electrolytically or by injecting 5,6-dihydroxytryptamine prevented rigidity without affecting tremor. Electrical stimulation of the dorsal raphe increased transiently the hindlimb tone of normal rats. The findings demonstrate that the monoamines, especially 5-HT, are differently involved in the mechanisms of tremor and rigidity produced by tremorine.

• Authors: S L Dickinson, P Slater
• Journal: Neuropharmacology (Neuropharmacology) Vol. 21 Issue 8 Pg. 787-94 (Aug 1982) ISSN: 0028-3908 [Print] England
• PMID: 7121751 (Publication Type: Journal Article)

Chemical References

• Hydroxydopamines
• Serotonin
• Tremorine
• Dopamine
• Norepinephrine

Topics

• Animals
• Dopamine (physiology)
• Electric Stimulation
• Female
• Hydroxydopamines (pharmacology)
• Muscle Rigidity (chemically induced, physiopathology)
• Neural Pathways (physiology)
• Norepinephrine (physiology)
• Raphe Nuclei (physiology)
• Rats
• Rats, Inbred Strains
• Serotonin (physiology)
• Tremor (chemically induced, physiopathology)
• Tremorine